Yes FvM.
I found that.
https://in.rsdelivers.com/product/n...-mount-current-transformer-10001/5374520.aspx
I will be using AC1020.
For 100 Ohms Burden resistor it gives 0.1V/A
It will give approx 0.25V/A if 250 Ohms Burden Resistor is used.
I will use the attached circuit to get 5V for 20A. Is this circuit correct or should I use a OpAmp like OPA342NA to amplify the voltage obtained with a lower value burden resistor ?
I think using OpAmp will be better because the Output of the OpAmp can be interfaced with ADC of PIC.
https://www.mouser.in/ProductDetail...=sGAEpiMZZMtCHixnSjNA6Mrdwin7F8A2mwe07DyOrAU=
Can the output of just a resistor connected with C.T. be connected directly to the ADC pin of PIC ?
Should I use a circuit as shown. Circuit with diode and capacitor ? Or should I use OpAmp with a diode at its output and a load resistor.
Attached is the PIC circuit I have designed. It uses rotary switch for pump current selection. How can I remove the rotary switch and implement auto calibration of current ?
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Edit:
Currently I have used PIC18F46K22 for the design. I want to implement auto calibration based on pump current. If I can't implement auto calibration method then I will port the code to 18F87K22 with a rotary switch for current selection.
Attached is the Proteus simulation.
RV1 pot can be varied. Pump rating is 180V-300V AC 50 Hz 1 Phase
For V < 185V Blue LED of RGB LED turns ON indicating Low voltage
For V between 185 and 260V Green LED of RGB LED turns ON indicating Normal Voltage.
For V > 260 V Red LED of RGB Led turns ON indicating Over voltage.
V / I Button is used to toggle the display to show Voltage or Current.
Voltage range is 0 to 300 V and current range is 0 to 30A
Jumper JP1 can be shorted to see the company name scrolling on the 7 Segment Display.
The system is designed for both domestic use and for farmers.
JP2 Jumper can be used to select domestic use or for farmers. If domestic use (JP2 shorted) then it enables the system to use 3 float switches for the overhead tank and a RGB led for level display. If used for farmers then JP2 can be left open and the user has to turn ON/OFF the pump manually using ON/OFF button (not yet coded). If JP2 is shorted (domestic use) then device will be in auto mode. Auto mode LED will turn ON. In auto mode the pump can be turned ON manually by pressing the ON/OFF button or the pump will turn ON automatically if water level is critical in overhead tank. In auto mode the pump cannot be turned OFF manually. It turns OFF automatically when overhead tank is full. In manual mode (agricultural use) the manual mode led will be ON (JP2 open).
JP3 is not yet coded.
JP4 is Jumper for selecting programming header or PIC connections.
RN2 is only for Proteus Simulation. It will not be present in real hardware.
In auto mode level switches can have 4 states. NO type float switches are used which close when water level rises.
When all float switches are open (water level critical) RED Led of RGB Led turns ON.
when SW1, SW2 and SW3 are closed (water level full) Green Led of RGB Led turns ON.
when SW1 is closed and SW2 and SW3 are open (water level low) Yellow Led of RGB Led turns ON (Red + Green = Yellow)
When SW1 and SW2 are closed and SW3 is open (water level medium) Blue Led of RGB Led turns ON.
When pump has to turn ON it checks the mains voltage. If mains voltage is normal then pump turns ON for 2 seconds and then current is measured. If current is not in the normal range (dry run or overload) then pump turns OFF. If current was low then Dry Run Led turns ON. If current was high then overload Led turns ON. Only after rectifying the error the pump turns ON again.
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@betwixt
Please provide me a simple circuit for interfacing AC1020 C.T. with 5V PIC. I want to use the full range of AC1020 that is 20A. Please use diode to convert the AC to DC for ADC measurement.
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I have designed this display. Where can I find such a 3-Digit RGB 7 Segment Display ? The attached file shows 1 digit 7 Segment display. It has 8 data lines and 3 (RGB) control lines.
We have to turn ON these cathodes to get the required colors
Red - R Cathode
Orange /Amber / Yellow - R and G Cathodes
Cyan - G and B cathodes
Blue - B Cathode
Violet / Purple - R and B Cathodes
I need somebody to manufacture such a 3 digit 7 segment display with 8 data lines and 3 * 3 = 9 control lines.
I need such a display to display data in different colors.
For example
If voltage is < 180 V I want to display the data in Blue color
If voltage is between 180 and 260 V I want to display data in Green color
If voltage is > 260 V I want to display data in Red color
I can't use this. This is not good.
https://www.adafruit.com/product/1399